//! 监控系统模块
//! 
//! 提供性能指标收集、健康检查和监控功能

pub mod metrics;
pub mod health;

use crate::Result;
use crate::types::{HealthStatus, ResourceUsage, SystemStats};
use std::collections::HashMap;
use std::time::SystemTime;

/// 监控管理器
pub struct MonitoringManager {
    /// 是否启用监控
    enabled: bool,
    /// 采集间隔（秒）
    collection_interval_secs: u64,
}

impl MonitoringManager {
    /// 创建监控管理器
    pub fn new(enabled: bool, collection_interval_secs: u64) -> Self {
        Self {
            enabled,
            collection_interval_secs,
        }
    }
    
    /// 启动监控服务
    pub async fn start(&self) -> Result<()> {
        if !self.enabled {
            return Ok(());
        }
        
        tracing::info!(
            "Starting monitoring service with interval: {}s",
            self.collection_interval_secs
        );
        
        // TODO: 启动后台监控任务
        // 1. 定期收集系统指标
        // 2. 检查组件健康状态
        // 3. 发送告警通知
        
        Ok(())
    }
    
    /// 停止监控服务
    pub async fn stop(&self) -> Result<()> {
        tracing::info!("Stopping monitoring service");
        Ok(())
    }
    
    /// 收集资源使用情况
    pub async fn collect_resource_usage(&self) -> Result<ResourceUsage> {
        // 临时实现 - 返回模拟数据
        Ok(ResourceUsage {
            cpu_percent: 25.5,
            memory_mb: 512,
            disk_mb: 1024,
            network_rx_bytes: 1048576,
            network_tx_bytes: 2097152,
            timestamp: SystemTime::now(),
        })
    }
    
    /// 执行健康检查
    pub async fn health_check(&self) -> Result<HealthStatus> {
        let start = std::time::Instant::now();
        
        // 模拟健康检查
        tokio::time::sleep(tokio::time::Duration::from_millis(10)).await;
        
        let response_time = start.elapsed();
        let mut details = HashMap::new();
        details.insert("version".to_string(), "0.1.0".to_string());
        details.insert("uptime".to_string(), "1h 30m".to_string());
        
        Ok(HealthStatus {
            healthy: true,
            checked_at: SystemTime::now(),
            response_time_ms: response_time.as_millis() as u64,
            error_message: None,
            details,
        })
    }
    
    /// 获取系统统计信息
    pub async fn get_system_stats(&self) -> Result<SystemStats> {
        // 临时实现 - 返回模拟数据
        Ok(SystemStats {
            total_sandboxes: 50,
            active_sandboxes: 30,
            pool_stats: HashMap::new(),
            language_distribution: HashMap::new(),
            system_load: 0.75,
            memory_usage_percent: 65.0,
            timestamp: SystemTime::now(),
        })
    }
    
    /// 导出Prometheus指标
    pub fn export_prometheus_metrics(&self) -> String {
        // 临时实现
        format!(
            "# HELP koda_sandboxes_total Total number of sandboxes\n\
             # TYPE koda_sandboxes_total gauge\n\
             koda_sandboxes_total 50\n\
             # HELP koda_sandboxes_active Active sandboxes\n\
             # TYPE koda_sandboxes_active gauge\n\
             koda_sandboxes_active 30\n"
        )
    }
}

impl Default for MonitoringManager {
    fn default() -> Self {
        Self::new(true, 30)
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    
    #[tokio::test]
    async fn test_monitoring_manager_creation() {
        let manager = MonitoringManager::new(true, 60);
        assert!(manager.enabled);
        assert_eq!(manager.collection_interval_secs, 60);
    }
    
    #[tokio::test]
    async fn test_health_check() {
        let manager = MonitoringManager::default();
        let health = manager.health_check().await.unwrap();
        
        assert!(health.healthy);
        assert!(health.response_time_ms < 100); // 应该很快
        assert!(health.error_message.is_none());
    }
    
    #[tokio::test]
    async fn test_resource_collection() {
        let manager = MonitoringManager::default();
        let usage = manager.collect_resource_usage().await.unwrap();
        
        assert!(usage.cpu_percent >= 0.0 && usage.cpu_percent <= 100.0);
        assert!(usage.memory_mb > 0);
    }
    
    #[test]
    fn test_prometheus_export() {
        let manager = MonitoringManager::default();
        let metrics = manager.export_prometheus_metrics();
        
        assert!(metrics.contains("koda_sandboxes_total"));
        assert!(metrics.contains("koda_sandboxes_active"));
    }
}